The ID-825 is a current production Narco VOR/LOC/Glideslope Indicator. The ID-825 has rectilinear meter movements, instead of pendulum, which makes it easier to read. This is especially nice when flying an ILS, since the needles stay perpendicular to each other throughout their range of travel. This feature helps the pilot to better determine the degree of correction needed to follow the approach accurately. The ID-825 is also TSO'd.